Well, those tech critics just need to wait for the current "social web" bubble to implode, and then we'll see people showing cardboards saying stuff like:

"will do community management for food!"

http://images2.wikia.nocookie.net/__cb20070820063441/uncyclo...

and then as the shares of Facebook, Twitter and even the almighty google drops, the tech unemployment raises in the valley and SF, engineers get evicted and then prices will lower!

They just need to stop complaining, be patient for a few years and that will happen…

…until the next tech bubble gets the valley crazy again ;-)